On most any cruise ship, passengers get frustrated by “chair hogs,” or people who try to claim a pool deck lounge chair for an extended period of time by leaving their belongings on it and then disappearing. Cruise lines discourage this behavior but it persists, especially on Carnival and Royal Caribbean cruise ships.

The outbreak happened on Royal Caribbean’s Radiance of the Seas, which set sail from Tampa, Florida, on Feb. 1.

Two major cruise lines have addressed a controversial hidden fee that has annoyed customers. Both Carnival Cruise and Royal Caribbean charge passengers for unreturned towels. All towels used at the pool or during execursions must be returned using your cabin number and room key.